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931.
932.
Circular genomes, being the largest proportion of sequenced genomes, play an important role in genome analysis. However, traditional 2D circular map only provides an overview and annotations of genome but does not offer feature-based comparison. For remedying these shortcomings, we developed 3D Genome Tuner, a hybrid of circular map and comparative map tools. Its capability of viewing comparisons between multiple circular maps in a 3D space offers great benefits to the study of comparative genomics. The pro...  相似文献   
933.
Spatial and temporal variation of fish assemblages were investigated seasonally from May 2007 to February 2008 across 11 study sites in a subtropical small stream, the Puxi Stream, of the Huangshan Mountain. Along the longitudinal gradient from headwater to downstream, fish species richness and abundance increased gradually, but then decreased significantly at the lower reaches. The highest species richness and abundance were observed in August and the lowest in February. Based on analysis of similarities (...  相似文献   
934.
A strong focus of ecological research for several decades has been to understand the factors underlying the variation in animal life-histories. In recent times, ecological studies have begun to show that oxidative stress may represent another important modulator of competitive trade-offs among fitness traits or of positively integrated patterns of traits. Therefore, incorporating mechanisms underlying oxidative physiology into evolutionary ecology has the potential to help understand variation in life-histo...  相似文献   
935.
Lamprey is a representative of the agnathans, the most ancient class of vertebrates. Parasitic lampreys secrete anticoagulant from their buccal glands and prevent blood coagulation of host fishes. We identified a buccal gland secretory protein-2 (BGSP-2) from a buccal gland cDNA library of Lampetra japonica. The full-length BGSP-2 gene was cloned and the recombinant BGSP-2 protein was generated. The role of BGSP-2 on lymphocyte proliferation was studied by examining its effects on human T lymphocytes. We found that lamprey BGSP-2 was able to effectively block the proliferation of T cells in vitro by inducing G_1/S cell cycle arrest. Furthermore, it inhibited the proliferation of human T lymphocytes stimulated by phytohemagglutinin (PHA) at a minimum concentration of 0.1μg/ml. Our data suggest that lamprey BGSP-2 is able to block the mitosis of human T lymphocytes at the G1/S point, and has the potential of anti-proliferative effect on PHA-activated T lymphocytes.  相似文献   
936.
在研究转基因香石竹品系月之霓裳(Moonshade)、月之伊人(Moonlite)中外源基因F3’5’H的表达中,本文克隆了F3’5’H全长基因1.5kb,构建获得工程菌株Escherichia coli BL21(DE3)(+F3'5'H)。SDS-PAGE分析的结果显示,该菌株高效表达出F3’5’H重组蛋白,约占菌体总蛋白的30%。用经纯化的F3’5’H重组蛋白作为抗原,制备F3’5’H重组蛋白的抗血清,经ELISA免疫学分析表明,该抗血清的效价为1:25600。Western blot结果表明F3’5’H重组蛋白具有良好的IgG结合活性,且抗血清与转基因香石竹品系月之霓裳和月之伊人中的外源基因F3’5’H所表达的蛋白发生明显的抗原抗体反应。这样,月之霓裳和月之伊人用于评价转基因香石竹品系的环境安全性在我国也得到了验证。  相似文献   
937.
This research was conducted to determine the optimum moisture content (MC) that gave maximum longevity to seeds. Three species were used to represent seeds with different dry matter reserves, which gives them different sorption properties: maize (Zea mays L.), elm (Ulmus pumila L.) and safflower (Carthamus tinctorius L.). The seeds of elm, safflower, and maize embryos with MC ranging from 0.00– 0.15 g H2O/g dry weight (DW) were stored at 35 °C for different periods of time. The results showed that the optim...  相似文献   
938.
The evolution of animal and plant vascular systems played a pivotal role in the advancement from simple to complex organisms, through the provision of a delivery system for the distribution  相似文献   
939.
本文旨在对雌性棕色田鼠(Lasiopodomys mandarinus)和昆明小鼠(Mus musculus)在慢性间歇性低氧条件下血象的变化进行比较,从而为地下生活鼠种血液系统对慢性间歇性低氧的应答对策的研究提供基础数据。采用实验氧舱对棕色田鼠和昆明小鼠进行每天4h、持续28d的慢性间歇性低氧(氧浓度10.0%)处理,然后对其血象进行了比较分析。结果显示:(1)常氧下棕色田鼠的红细胞计数(red blood cell count,RBC)显著高于昆明小鼠,而红细胞平均体积(mean corpuscular volume,MCV)则显著小于昆明小鼠,慢性间歇性低氧处理后昆明小鼠的MCV和红细胞压积(hematocrit,HCT)显著增加,而棕色田鼠MCV和HCT无明显影响;(2)常氧条件下棕色田鼠的平均血红蛋白含量(mean corpuscular hemoglobin,MCH)显著低于昆明小鼠,而平均血红蛋白浓度(mean corpuscular hemoglobin concentration,MCHC)则显著高于昆明小鼠,慢性低氧处理后昆明小鼠血红蛋白(hemoglobin,HGB)含量和MCH均显著增加,而在棕色田鼠仅出现MCH的明显增加;(3)常氧条件下棕色田鼠的白细胞计数(white blood cell count,WBC)和血小板(platelet,PLT)都显著低于昆明小鼠,慢性低氧处理后棕色田鼠和昆明小鼠的WBC和PLT均未发生显著变化。以上结果表明,棕色田鼠作为地下生活鼠种,对低氧环境具有较好的耐受性,其血液系统对低氧胁迫的应答机制与地面生活鼠种昆明小鼠不同。  相似文献   
940.
The rice indica/japonica hybrid shows strong heterosis.However,such inter-subspecific hybrid can't be directly used in rice production due to its low spikelet fertility.The S5 locus was proved to be associated with fertility of indica/japonica hybrid and its S5n allele from wide-compatibility variety (WCV) is capable to overcome fertility barrier.In the present study,we reported the causal sites in the S5 locus responsible for compatibility of indica/japonica hybrid.Fine-mapping of the S5 locus using the 11...  相似文献   
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